Wireless carriers, such as cellular telephone service providers, are currently able to determine the location of a wireless device. For example, a cellular telephone user can be tracked by determining the signal strength that is being received by nearby transceiver cells and triangulating the user's position. Also GPS is used to determine positions of mobile devices. However if a person is inside a building this can affect GPS and cellular coverage, leading to distortions in the positioning of a user. What is needed is a method of tracking wireless devices to a greater degree of accuracy.
The prior art knows from WO 2008/082783 A1 a method, apparatus, and electronic device for determining a location of a mobile device. A receiver asynchronously receives an access signal from at least three access points of a wireless local area network with the mobile device. A processor measures access signal strength for the access signal for each access point. A transmitter transmits the access signal strengths to a location server to determine the location of the mobile device. The prior art knows from US 2004/0203872 A1 a mobile client device that determines the mobile device's distance from a transmitting device by measuring the strength of a wireless signal. However, there is no possibility for the mobile client device to locate mobile devices from which the mobile client device does not receive adequate wireless signals, e.g. due to walls between the mobile devices.
The drawback of the prior art is that fixed access points transmitting access signals are needed and/or that a transmission of adequate wireless signals between the mobile devices must be possible. Therefore, the realization is comparatively expensive and inflexible referring to the area in which the mobile device is located.
This is only one drawback of the prior art that is solved by the present invention explained in the following.